Everything you need to know before manufacturing.

Proto&Go! allows you to request a quote and order custom parts from an online platform. You upload the 3D model, select the process, material, finish, and quantity, and an engineering team reviews the part. Afterwards, you receive a quote with the price and lead time to decide whether to confirm the order.

Proto&Go! works with engineers, designers, universities, R&D centers, maintenance teams, creative studios, and startups. The service allows manufacturing prototypes and short runs of parts to develop products, verify designs, or meet manufacturing needs.

Proto&Go! manages manufacturing using the resources of the i-mas group and a network of approved manufacturers, depending on the part, process, and quantity. All parts pass through Proto&Go!'s quality control before shipping. Your contact throughout the order is always Proto&Go!.

Proto&Go! offers four manufacturing processes:

• CNC machining: 3, 4, and 5-axis milling and turning.
• 3D printing with HP Multi Jet Fusion, in PA12 and flexible TPA.
• Vacuum casting of polyurethane in silicone molds.
• Laser cutting and CNC bending of sheet metal.

The engineering team can help you select the process when preparing the quote.

Proto&Go! is located at C/ Castelló, 19, 08110 Montcada i Reixac, Barcelona. We ship orders to Spain and the rest of the world. You can check the location on the contact page.

Proto&Go! restricts access to your files to the personnel and collaborators necessary to manufacture the parts. Both parties sign non-disclosure agreements to protect proprietary information. If your project requires it, you can request a specific confidentiality agreement, also known as an NDA.

Yes. The Proto&Go! engineering team can review the material, process, and part requirements with you when preparing the quote. Email info@protoandgo.com or call +34 932 20 71 04 to submit your inquiry.

Proto&Go! is the online manufacturing platform of i-mas, an industrial group based in Barcelona with over 20 years of experience in mechanical engineering, product development, and manufacturing. It combines online quote requests with a review of each part by an engineering team.

Proto&Go! serves customers in Spanish, English, French, and Italian. The website, design guides, and ordering platform are available in these four languages.

Monday through Thursday, 9:00 to 18:00, and Fridays, 9:00 to 15:00, Central European Time. You can email info@protoandgo.com or call +34 932 20 71 04.

To get a quote and manufacture with Proto&Go!, you need a 3D model for each part. If you only have a sketch, a 2D drawing, or an idea, the i-mas engineering team can help you create that model. Email info@protoandgo.com to inquire about the modeling service.

Proto&Go! sends the quote within 24 hours of receiving the request with the 3D file and manufacturing requirements. The quote indicates the price and lead time for each part. You can request it from the Proto&Go! platform.

To request a quote on the Proto&Go! platform, you need a company email and a 3D model per part. Specify the process, material, finish, and quantity.

• Send STEP (.stp, .step) or a native supported format: SLDPRT, X_T, X_B, IPT, CATPART, PRT, SAT, or 3DM. For 3D printing, STL is also supported.
• Attach a PDF drawing if there are threads, inserts, or specific tolerances.

If the Proto&Go! platform fails to load, update Chrome, Edge, or Firefox, or try one of those browsers. If the issue persists, email info@protoandgo.com detailing what happens when you try to access it.

Proto&Go! accepts one 3D model per part in STEP (.stp, .step), SLDPRT, X_T, X_B, IPT, CATPART, PRT, SAT, or 3DM. STL files are accepted only for 3D printing. A 2D file does not replace the 3D model; you can attach a PDF to indicate threads, inserts, tolerances, or other requirements.

At Proto&Go! you can send an STL for 3D printing. For CNC machining, silicone molds, or sheet metal, send STEP or one of the supported native formats. STL represents the surface via triangles; for those other processes, export the original model from your CAD software.

Ensure the file contains a single part, without other assembly components, screws, or commercial elements. Verify that it uses an accepted format and opens correctly in your CAD software. If needed, re-export the model to STEP. If the error persists, contact info@protoandgo.com.

Proto&Go! manufactures from a single unit to runs of thousands of parts, depending on the process and design. When requesting a quote, you can compare up to three different quantities. This allows you to evaluate the cost of the prototype and a potential run with the same requirements.

Proto&Go! prices are shown excluding VAT. When adding parts to the cart, you can view the breakdown of tax and the total before confirming the order.

The 3D model is sufficient to quote and manufacture a part without additional requirements. Attach a PDF drawing if you need threads, inserts, specific tolerances, or to indicate any geometric detail. To define functional dimensions, you can use the tolerance calculators and fits.

STEP (.stp, .step) is a neutral format that preserves the exact geometry of the part and opens in any CAD software. That is why it is the safest option to quote and manufacture via CNC machining, silicone molds, or sheet metal. If you work with SolidWorks, Inventor, CATIA, Creo, NX, or Rhino, you can also upload the native file.

No. Export the 3D model to STEP or upload a supported native format: SLDPRT, X_T, X_B, IPT, CATPART, PRT, SAT, or 3DM. A 2D drawing in DXF is also not suitable for sheet metal: the part is uploaded already bent in 3D and the development is calculated from the model.

No. Each file must contain a single part. If your design is an assembly, export each part you want to manufacture to an independent file and upload them separately, without screws or commercial elements. If the parts must fit together, indicate the fit dimensions in a PDF drawing.

Attach a PDF drawing assigned to the part when there is information not shown by the 3D model: threads and their metric, inserts, welds, or tolerances tighter than the general tolerance. If there are no special requirements, the 3D model is sufficient and the general tolerance applies.

On the resources page, you can enter the extension or drag and drop the file to see which processes accept it: STEP and native formats for all, STL only for 3D printing, and PDF only as a supporting drawing. Only the file name is read; nothing is uploaded.

You can check your quotes and orders in the customer area of Proto&Go!. Access using the username and password you received by email when requesting the quote. In that same account, you can also review your shipping and billing details.

If you need to change the 3D file of a confirmed order, call Proto&Go! at +34 932 20 71 04 within the first 24 hours. The team will check if the modification can still be applied; the change is not guaranteed. After that deadline, the order can no longer be modified because it enters production.

Enter the customer area of Proto&Go!, select the parts, and add them to the cart with the quantity of each. Use the "Print quote" option in the cart to get a copy of the offer.

Proto&Go! accepts bank transfer, credit card, and PayPal. It also offers deferred payment for 30 days to clients who request it and meet the contract and credit approval conditions.

To request 30-day payment at Proto&Go!, you must meet these conditions:

• Have placed orders totaling at least 3,000 € in the last 12 months.
• Obtain a favorable result from an external credit insurance study, with insurable credit exceeding the total of orders for a full deferred payment period.

Proto&Go! uses protective material against impacts and scratches. Parts are bagged and packaged individually, except for very small ones. A label allows identification of the order, file, material, and quantity to maintain traceability.

Proto&Go! lead times are counted in working days from order confirmation:

• CNC machining and sheet metal: from 8 days.
• 3D printing: from 5 days.
• Silicone molds: from 10 days.

The quote confirms the lead time for each part according to its geometry, material, finish, and quantity.

Proto&Go! ships orders with Nacex when the delivery address is in Spain. For deliveries to other countries, it uses DHL.

Proto&Go! manufactures from a single unit. The minimum order amount is 60 €; if the parts total less, the difference is added up to that amount. The minimum manufacturing cost indicated is 46 € for CNC machining and 9 € for 3D printing. The quote confirms the order amount.

Shipping costs from Proto&Go! depend on the destination:

• Spain: 9 €. Free shipping for orders over 150 €.
• European Union: 15 €. Free shipping for orders over 150 €.
• Outside the European Union: 45 €. Free shipping for orders over 250 €.

Transport is 24 hours in Spain, with delivery before 19:00; 24 hours in the EU, or 48 in some remote areas; and 48 to 72 hours in other countries. These times correspond to transport, once the parts have been manufactured.

To request cancellation of a Proto&Go! order, call +34 932 20 71 04 within the first 24 hours from confirmation. The team will check if cancellation is still possible; cancellation is not guaranteed. After that deadline, the order can no longer be cancelled as it enters production.

If the package arrives with visible damage, indicate it on the carrier's receipt and contact Proto&Go! Customer Service at info@protoandgo.com. Explain the damage you detected so the team can review the incident.

Report the incident to info@protoandgo.com within 48 hours following receipt and indicate which requirements the parts do not meet. The team will ask you to package them for collection and review the problem. If non-conformity is confirmed, they will be corrected or the order repeated if it cannot be reprocessed, with no return or reprocessing cost for you.

The price of a CNC machined part depends mainly on machine time: geometry, material, setups, tolerances, finish, and quantity. At Proto&Go! you upload the 3D model and receive the quote with price and lead time in 24 hours. The minimum order is 60 € and the minimum manufacturing cost for CNC machining is 46 €.

At Proto&Go!, you receive the quote within 24 hours and machined parts within 8 working days from order confirmation. The lead time for each part depends on geometry, material, finish, and quantity, and is displayed in the quote. Shipping is then added: 24 hours in Spain.

Proto&Go! machines from a single unit. When requesting a quote, you can compare up to three quantities to see how the price per part decreases in a short run. For long runs of machining, you can consult the machining team of i-mas.

CNC machining produces a part by removing material from a block or bar using computer-controlled cutting tools. From the 3D model, toolpaths are programmed, and the machine mills or turns until the geometry is achieved. It is suitable for functional parts in metal and engineering plastics, for both prototypes and short runs.

With 3-axis machining, the tool moves in X, Y, and Z over the fixed part: this is the most economical option for plates, pockets, and brackets. The fourth axis adds a rotation to machine multiple faces without re-clamping. With 5 axes, the table tilts and rotates, allowing complex geometries and free-form surfaces in a single setup. Proto&Go! selects the process based on the geometry to optimize the price.

Turning is the fastest and most economical option for rotational parts: shafts, bushings, bolts, or fittings. The part rotates and the tool advances in X and Z. If the round part also has flat surfaces, side holes, or grooves, turning and milling are combined.

CNC machining delivers the part in the final material, with better tolerances and finish: it is the option for functional prototypes in metal or engineering plastics. 3D printing is faster and more economical for complex geometries, hollow parts, or multiple design versions. At Proto&Go!, 3D printing in PA12 is delivered within 5 working days, while machining starts from 8.

For low quantities in metal or engineering plastics, CNC machining is the direct option. For short runs of plastic parts with a product-like appearance, silicone molds with polyurethane casting reduce the price per part. For thousands of plastic parts, injection molding is usually cost-effective because the mold cost is amortized. At Proto&Go!, we help you compare when preparing the quote.

One 3D model per part in STEP or a native format: SLDPRT, X_T, X_B, IPT, CATPART, PRT, SAT, or 3DM. STL is not suitable for machining, as it describes the surface with triangles and loses exact geometry. If you only have a sketch, the i-mas engineering team can create the model.

No. At Proto&Go!, the 3D model is sufficient for quoting and manufacturing, with general tolerances applied to all dimensions. A PDF is added only to indicate threads or inserts, which the 3D model does not show.

At Proto&Go!, the online manufacturing platform of the i-mas industrial group. You upload the 3D model to the Proto&Go! platform, select material, finish, and quantity, and receive the quote within 24 hours. An engineering team reviews each part, and all pass quality control before shipping.

At Proto&Go! you receive the quote within 24 hours and the 3D printed parts within 5 working days from order confirmation. The lead time for each part depends on size, quantity, and finish, and is listed in the quote.

Proto&Go! prints using HP Multi Jet Fusion technology in two materials. PA12 is a rigid and tough nylon that resists wear, oils, and greases, with a natural gray or dyed black finish. TPA 90A is flexible like rubber and recovers its shape: it is suitable for bellows, seals, and grips.

The tolerance is ±0.3 mm for measurements up to 100 mm and ±0.3 % above that. The part can measure up to 380 × 284 × 380 mm, although it is recommended not to exceed 356 × 280 × 356 mm to avoid edge effects, and a minimum of 3 × 3 × 3 mm. If it is larger, it is divided into parts.

Yes. HP Multi Jet Fusion 3D printing does not require tooling or molds, so you can order from 1 unit and go from prototype to series with the same file. The price depends mainly on the volume of powder the part occupies: emptying thick areas reduces it.

Multi Jet Fusion (MJF) is an industrial 3D printing technology from HP. A roller extends a layer of 0.08 mm powder, a head applies agents over the part section and heat fuses it; the platform lowers and the process repeats layer by layer. The unfused powder supports the part, so supports are not needed.

MJF and SLS fuse nylon powder without supports; MJF is faster and produces parts with more homogeneous properties. SLA cures a liquid photopolymer with light and achieves the best surface detail, but its parts are more fragile and degrade with light. FDM deposits fused filament: it is the simplest and most economical, with lower resolution. Proto&Go! prints in MJF for its balance between strength, detail, and lead time.

They are functional. PA12 parts printed via MJF are used in prototypes that are assembled and tested, as well as in final runs for drones, robotics, custom machinery, medical devices, or consumer products. If the part needs to be transparent or have a finished product appearance, consider CNC machining or vacuum casting.

It is a process for producing prototypes and short runs of polyurethane parts. A master model, printed or machined, is wrapped in liquid silicone, and once cured, the mold is cut into two halves to remove the master. Then, the polyurethane is cast in a vacuum chamber to avoid bubbles, cured in an oven, and the part is demolded.

Each silicone mold yields approximately 20 parts, depending on the design. Vacuum casting is designed for prototypes and short runs, from 10 to 300 units, manufacturing the necessary molds. Above 300 parts, injection molding usually becomes more cost-effective.

At Proto&Go!, you receive the quote within 24 hours and the parts within 10 working days. An injection mold takes several weeks, so vacuum casting delivers your first production parts much sooner.

Rigid polyurethanes, similar to ABS or polycarbonate; flexible ones, similar to silicone, TPE, or NBR; and transparent ones, rigid like PMMA or flexible. Elastomers range from Shore A 30 to Shore A 90. PU parts are as resistant or more than injected ones and more durable than 3D printed parts.

Yes. Polyurethane is pigmented in bulk in a RAL or Pantone color, with a matte, satin, or glossy finish: the color penetrates the part and does not wear off with friction, although it has some color tolerance. It can also be painted in RAL or Pantone or left transparent. The result is equivalent to the color of an injected part.

Injection molding requires a steel or aluminum mold, which takes several weeks and costs much more, but spreads its cost over large runs. Vacuum casting uses silicone molds, which are much cheaper, and delivers parts with a finished product appearance within 10 working days. That is why it is used for advanced prototypes, market testing, and initial production runs while the injection mold is being manufactured.

Proto&Go! cuts and bends carbon steel, stainless steel, aluminum, copper and brass sheet metal, in thicknesses from 0.3 to 15 mm depending on the material; bending is confirmed for each metal and thickness. Each material has its datasheet with properties and finishes in the materials catalog.

At Proto&Go!, you receive the quote within 24 hours and sheet metal parts from 8 working days after confirming the order. Parts are manufactured from 1 unit and without tooling. The lead time for each part appears in the quote.

One 3D model per part, with the part already bent, in STEP or a native format: SLDPRT, X_T, X_B, IPT, CATPART, PRT, SAT, or 3DM. The development is calculated from the 3D. The platform does not accept DXF or STL files.

Yes, if the part requires it. Since the 3D model does not indicate the thread metric, the insert type, or the welds, specify them in a dedicated PDF drawing assigned to the part.

The same as machining: painting in RAL color, zinc plating, anodizing, sandblasting, polishing, bluing, or chrome/nickel plating. Each finish depends on the material: anodizing is for aluminum, and bluing and zinc plating are for steel.

The material datasheet includes 27, among them aluminum, stainless steel, brass, ABS, POM, PA12, and polyurethane. You can filter by process and part characteristics. The platform displays the available materials for the technology you choose.

For a plastic prototype, you can compare machined ABS and PA12 in 3D printing. If you are looking for a housing that can be painted, ABS is an option. For a metal prototype, you can consider aluminum. The cost depends on the design and quantity; consult the material datasheet and confirm your choice when requesting a quote.

Yes, you can check its availability with Proto&Go!. Indicate the exact material you need in the "Observations" field of the request or write to info@protoandgo.com. If the platform forces you to choose another option, clarify the difference in that field. The team will confirm if they can manufacture it and the lead time.

Proto&Go! machines metals such as aluminum, stainless steel, carbon steel, copper, brass, and bronze, and engineering plastics like POM, polyamide, polycarbonate, PMMA, PEEK, or PTFE. Each material has its datasheet with properties and applications in the materials catalog.

6082 and 6061 are the most common: they machine well, resist corrosion, and allow anodizing. 7075 is much stronger and is reserved for highly requested parts, with a higher price. 5083 stands out in marine environments. If you are unsure, 6082 is a good starting point.

POM or acetal is the easiest to machine and performs very well in parts with friction, such as gears or guides. Nylon withstands impacts and wear but absorbs moisture. Polycarbonate and PMMA are suitable for transparent parts. For high temperatures or demanding chemical environments, the reference is PEEK.

For a functional prototype, choose the material based on what you need to validate: aluminum for lightweight mechanical parts; POM for fits and sliding; and PA12 in 3D printing for complex shapes. ABS is an option for housings and presentation prototypes that can subsequently be painted.

Machined ABS is a good option for housings, covers, and presentation prototypes. It can be painted to achieve the desired color and appearance, with matte, satin, or glossy finishes. For runs of several units, you can also consider rigid polyurethane (PU) obtained via vacuum casting in silicone molds. Indicate the color and finish when requesting the quote; painting is quoted separately.

PMMA is an option for display parts and polycarbonate (PC) when impact resistance is also important. In both cases, the final transparency depends on the finish. For small runs of transparent parts, you can also consider transparent polyurethane in a silicone mold.

To manufacture a flexible part, you can use TPA in 3D printing or flexible polyurethane (PU) in a silicone mold. The choice depends on the quantity, the finish, and the hardness you need. Thickness and shape also influence how much the part flexes.

In 3D printing, the price per part usually varies little with quantity: manufacturing more units does not imply significant savings. In CNC machining, spreading the setup across several parts usually reduces the price per unit more. In silicone molds, the cost of the pattern and the mold is also spread.

The alloy is selected based on the part's function and the loads, humidity, or temperature it must withstand. Specify these conditions and upload your 3D file so the Proto&Go! team can propose an appropriate option. If the drawing requires a specific alloy, include it in the request.

You can consult Proto&Go! if you need to manufacture a part in a material or alloy that does not appear in the catalog. Write to info@protoandgo.com indicating the material you need so we can check its availability and lead time.

Machined plastic useful for validating shapes, fits, and exterior appearance. It admits painting and can reproduce the appearance of a product housing. Chrome plating requires a suitable grade and a specific process: confirm availability for the part. Exterior exposure requires evaluating UV resistance.

Steel for shafts, bolts, and mechanical components. Its strength, hardness, and weldability depend on carbon content and heat treatment. No single hardness or strength is assigned to the entire family. 42CrMo4 is an alloy steel and must be specified separately. Weldability and finish depend on the grade.

Family of steels with at least 10.5% chromium. Grades 304 and 316L offer good corrosion resistance; the choice depends on the working environment. Cold forming can increase the magnetism of certain austenitic stainless steels. After welding, pickling or passivation may be required to restore corrosion resistance.

Thermoset phenolic resin, typically in semi-finished goods reinforced with paper or fabric. The grade determines the balance between insulation and mechanical strength. Confirm the type of reinforcement and the density of the semi-finished product. Continuous use temperature and moisture absorption depend on the grade.

Family of copper alloys, typically with tin. Grades for bearings are used in parts subjected to friction and wear. Reference density for comparison. The composition of the bronze determines its properties, necessary lubrication, and response to the environment.

Metal with high electrical and thermal conductivity. Suitable for transferring current or heat; it is machined by selecting appropriate tools and conditions. Purity and grade change conductivity and machinability. The surface can oxidize and form patina.

High-density polyethylene for lightweight parts, resistant to impact and numerous chemicals. It has lower stiffness than structural engineering plastics. HDPE is not equivalent to PE-UHMW: the latter is a distinct option for demanding wear applications. HDPE is not proposed as a general material for load-bearing shafts.

Copper and zinc alloy with a golden tone. It offers good machinability in suitable grades and is used in mechanical parts and decorative components. Behavior in salt water depends on the alloy: some brasses suffer dezincification. For that application, a suitable grade must be specified.

Polyamide for Multi Jet Fusion 3D printing, suitable for functional prototypes and end-use components. It allows complex geometries without dedicated supports. Reference: HP 3D HR PA 12. The 175 °C corresponds to deformation under load (HDT) at 0.45 MPa; at 1.82 MPa it is 95 °C. These are not continuous use temperatures.

Tough polyamide, wear-resistant, and appropriate for guiding elements. It absorbs moisture, which modifies its dimensions and properties. Reference: natural extruded PA6. Values for a variant with glass fiber are not the same; in precision fits, moisture must be considered.

Glass fiber reinforced PBT with 30 % fiber for components requiring stiffness and dimensional stability. Its behavior depends on the semi-finished product and fiber orientation. Reference: semi-finished TECADUR PBT GF30. The grade, process, and fiber direction change properties; values from an injection molded test specimen cannot be extrapolated.

Transparent polycarbonate with good impact resistance. Machining leaves surface marks; polishing improves the clarity of optical areas. Weather resistance requires an appropriate grade or UV protection. Solvents can cause stress cracking.

High-performance thermoplastic for parts subjected to heat, load, and chemical agents. It offers good stability and mechanical resistance in demanding conditions. The admissible temperature depends on the load and duration. For medical contact, a specific grade and validation are required.

Amber-colored thermoplastic with good heat deflection temperature and electrical insulation. Suitable for dimensionally stable components subjected to temperature. Reference: natural PEI without reinforcement. The translucent amber is not equivalent to colorless optical transparency; the GF30 grade has other properties.

Semi-crystalline and opaque PET for machining, with good dimensional stability and wear resistance. It is used in guide elements and mechanical parts. This datasheet corresponds to machinable PET. Amorphous PET for packaging and other transparent products is a different presentation. Check chemical compatibility and compatibility with hot water.

Transparent plastic for parts where clarity and visual appearance are paramount. It can be machined and polished to obtain good quality optical surfaces. Avoid generalizations regarding chemical or impact resistance: it depends on the agent and the grade. It does not automatically substitute for polycarbonate safety protection.

Rigid and stable plastic with low moisture absorption and good sliding behavior. Suitable for mechanisms and precision parts. Delrin is a brand of POM-H, not a synonym for all POMs. For chemical agents, concentration and temperature must be checked; conductive variants are not insulators.

Lightweight polypropylene with good resistance to numerous acids and bases. It is useful for chemical components and parts with moderate mechanical requirements. It does not resist all solvents. Concentration, temperature, and load determine compatibility; its stiffness is lower than that of POM or PET.

Thermoplastic for components subjected to chemical agents and high temperatures. It presents low moisture absorption and good dimensional stability. The continuous temperature must be confirmed for the specific grade, load, and duration. Variants with fiber have other properties.

Fluoropolymer with low friction, good electrical insulation, and broad chemical resistance. Suitable for sealing and sliding when deformation under load is controlled. PTFE can deform slowly under load (creep). PTFE with glass or bronze has different properties; they must be selected based on load and wear.

Cast polyurethane combining elasticity and transparency for prototypes and pre-production runs with a product-like appearance. Catalog density range is indicative. Hardness, clarity, UV aging, and chemical resistance depend on the polyurethane resin, thickness, and curing.

Cast elastic polyurethane for pre-production runs with product-like feel, color, and texture. The formulation allows adapting hardness to the desired behavior. Catalog density range is indicative. Resistance to oils, tearing, cold, and heat must be confirmed for the selected polyurethane resin.

Cast polyurethane for transparent pre-production runs and visual validation. Clarity depends on the polyurethane resin, mold, thickness, and absence of bubbles. Catalog density range is indicative, pending the chosen polyurethane resin. UV stability and temperature depend on the formulation; they are not guaranteed for the entire family.

Molded-in silicone polyurethane to reproduce shapes, textures, and details of a pre-production run. The polyurethane resin is selected based on the desired behavior and appearance. Catalog density range is indicative. Tensile strength, hardness, and temperature require a specific polyurethane resin reference; they are not single values for all rigid PUs.

Unplasticized PVC for machining: rigid, insulating, and resistant to numerous chemical agents. Used in installation components and industrial equipment. This datasheet corresponds to rigid PVC (PVC-U). Flexible cable covers and hoses use different plasticized formulations.

Polyamide elastomer for Multi Jet Fusion, appropriate for flexible parts that recover their shape. Geometry and thickness influence perceived flexibility. The 90A designation indicates nominal Shore A hardness, not tensile strength. Final values depend on the powder and printing parameters.

If you do not specify tolerances, Proto&Go! applies the general ISO 2768-f tolerance for metals and ISO 2768-m for plastics. For a 25 mm dimension in metal, that means ±0.10 mm, the thickness of two sheets. This is sufficient for most functional parts, housings, supports, and prototypes.

A tighter tolerance than the general one requires slower finishing passes, more careful measurement, and more rejected parts. That is why it is best reserved for dimensions that truly need it, such as a bearing housing. For the rest, the general tolerance is already very fine and keeps the price low.

For specific functional dimensions, Proto&Go! can reach an IT7 quality in metals, about 21 microns for a 25 mm dimension, and IT11 for plastics. Plastics expand and absorb moisture, so it is not advisable to demand metal-level precision. If a part needs such a fit, mention it to the engineering team when requesting the quote.

A machined part shows fine tool marks. At Proto&Go!, surfaces up to Ra 1.6 µm are achieved, about forty times finer than a hair. If you are looking for a uniform appearance, sandblasting or anodizing masks the marks.

H7 defines the size tolerance of a hole. The letter H fixes the lower deviation at zero: the minimum size matches the nominal. The grade 7 determines the tolerance range according to the diameter. For example, a Ø25 H7 hole accepts sizes between 25.000 and 25.021 mm.

Uppercase letters identify hole tolerances and lowercase letters identify shafts. In H7, the hole can be equal to or larger than the nominal size; in h6, the shaft can be equal to or smaller. For the same nominal diameter, the H7/h6 combination has a minimum clearance of zero. Grades 7 and 6 determine the range of each tolerance.

In the Proto&Go! tolerance calculator, select shaft or hole and enter the nominal size, position, and tolerance grade. You will obtain the maximum and minimum sizes in millimeters and the deviations in microns. The table allows comparing the available grades for that position. The tool covers nominal sizes greater than zero up to 500 mm.

H7/g6 is a clearance fit: the g6 shaft is smaller than the H7 hole for the same nominal diameter. At Ø25 mm, the diametral clearance ranges from 7 to 41 µm, that is, from 0.007 to 0.041 mm. For another diameter, recalculate the limits of both parts.

In a clearance fit, the hole is equal to or larger than the shaft. In an interference fit, the shaft is equal to or larger than the hole, and assembly may require pressure or a temperature difference. In a transition fit, clearance or interference may occur depending on the actual measurements. Parts with the same nominal size are always compared.

In the hole-basis system, a hole with H tolerance position is maintained, and the shaft tolerance is selected to obtain the required fit. For example, H7/g6 provides clearance, H7/k6 may provide clearance or interference, and H7/p6 provides interference for a nominal diameter of 25 mm. The choice depends on how the joint must function and be assembled.

ISO 2768 sets general tolerances for dimensions that do not have a specified tolerance. Part 1 covers linear and angular measurements with four classes: f (fine), m (medium), c (coarse), and v (very coarse). Part 2 covers general geometric tolerances with classes H, K, and L. Thus, the drawing only needs explicit tolerances on functional dimensions.

Class f (fine) is tighter than class m (medium). For linear dimensions:

• Over 6 up to 30 mm: ±0.1 mm in f and ±0.2 mm in m.
• Over 30 up to 120 mm: ±0.15 mm in f and ±0.3 mm in m.
• Over 120 up to 400 mm: ±0.2 mm in f and ±0.5 mm in m.

If you do not specify tolerances, Proto&Go! applies ISO 2768-f for machined metal parts and ISO 2768-m for plastic.

±0.3 mm: the dimension can measure between 49.7 and 50.3 mm. For the same dimension, the fine class (f) allows ±0.15 mm and the coarse class (c), ±0.8 mm. All dimensions over 30 up to 120 mm share these values.

It combines the two parts of the standard: «m» is the medium class for linear and angular dimensions (ISO 2768-1) and «K» is the intermediate class for general geometric tolerances, such as straightness, flatness, perpendicularity, or symmetry (ISO 2768-2). It applies to all dimensions and geometries that do not have a specified tolerance.

ISO 286 IT grades define the tolerance width according to the nominal size, from IT01 to IT18: the lower the number, the tighter the tolerance. For a 25 mm dimension, IT7 is 21 µm; IT6, 13 µm; IT8, 33 µm, and IT11, 130 µm. In machining, Proto&Go! achieves IT7 for functional metal dimensions and IT11 for plastic.

An Ø20 h6 shaft allows measurements between 19.987 and 20.000 mm: upper deviation 0 and lower deviation −13 µm. The letter h fixes the maximum measurement at the nominal size and grade 6 provides a width of 13 µm for diameters over 18 up to 30 mm. You can calculate other measurements with the tolerance calculator.

An Ø25 g6 shaft measures between 24.980 and 24.993 mm, with deviations of −20 and −7 µm. It always stays below the nominal size; therefore, with an H7 hole, it forms a clearance fit of 7 to 41 µm.

An Ø10 H7 hole allows measurements between 10.000 and 10.015 mm. The letter H sets the minimum measurement at the nominal size and grade 7 provides a width of 15 µm for diameters over 6 up to 10 mm.

They have the same width but in opposite directions. An H7 hole can be equal to or greater than the nominal size; an h7 shaft, equal to or less than. For Ø25 mm, H7 ranges from 25.000 to 25.021 mm and h7, from 24.979 to 25.000 mm.

In the hole-basis system the usual starting point is H7/p6, a light interference fit for fixed bushings pressed in. For a permanent joint, pressed or shrink-fitted, H7/s6 gives more interference. At Ø25 mm, H7/p6 has an interference of 1 to 35 µm and H7/s6, of 14 to 48 µm. Check it for your diameter with the fit calculator.

For precise and smooth sliding, H7/g6 is typically used, with a clearance of 7 to 41 µm for Ø25 mm. For shafts rotating at medium speed with lubrication, H8/f7 allows more clearance: 20 to 74 µm for Ø25 mm. If the part only needs to be centered and removed by hand, H7/h6 has a minimum clearance of zero.

It depends on which ring rotates relative to the load, the size, and the bearing manufacturer. In the most common case, a rotating shaft with a rigid ball bearing and normal load, SKF, NTN, and Schaeffler recommend the shaft in k5 for diameters of about 18 to 100 mm; j6 or js6 for light loads, and m5 or m6 for larger diameters or high loads. The housing, with the outer ring fixed relative to the load, is usually H7; if the load changes direction, J7 or K7. Qualities 5 and 6 of the shaft usually require grinding. Confirm the fit in the manufacturer's catalog and indicate it on the part PDF drawing.

In the shaft-basis system, the shaft maintains position h, with the maximum size equal to the nominal, and the hole tolerance is changed to achieve clearance, transition, or interference. In the hole-basis system, the hole is fixed in H and the shaft is selected. The hole-basis system is the most common, because holes are manufactured and verified with fixed measuring tools and gauges, and it is simpler to vary the shaft.

Dimensional tolerance limits the size of a dimension, for example Ø25 H7 or 40 ±0.1 mm. Geometric tolerance limits the form, orientation, or position: flatness, cylindricity, perpendicularity, parallelism, or position of a drilled hole, according to ISO 1101. Proto&Go! calculators solve dimensional tolerances; geometric tolerances are indicated on the part PDF drawing.

Attach a PDF drawing assigned to the part and mark only the dimensions that need it, with their tolerance, for example Ø12 H7 or 30 ±0.02 mm. The rest of the dimensions are machined with the general tolerance. Reserving tight tolerances for functional dimensions avoids increasing the part cost.

The standard tolerance for vacuum casting is ±0.3 mm for dimensions up to 100 mm and ±0.3 % for larger dimensions. Polyurethane shrinks by approximately 0.15 %, and precision also depends on the master, the silicone mold, the polyurethane resin, and the geometry: thick walls and long, flat parts warp more. If a dimension requires higher precision, indicate it in the PDF drawing, and the engineering team will confirm feasibility when preparing the quote.

A micron (µm) is one-thousandth of a millimeter: 0.001 mm. A sheet of paper measures about 100 µm in thickness, and a hair, about 70 µm. Therefore, an IT7 tolerance of 21 µm on a 25 mm diameter is less than one-third the thickness of a hair.

Yes. The tolerance calculator and the fit calculator are free and do not require registration. They cover shafts and holes with nominal sizes greater than 0 up to 500 mm, including ISO 286-1 positions and qualities.

What influences most is the design. Leave general tolerances on non-functional dimensions, use internal radii of at least one-third the depth, avoid thin walls and very deep pockets, choose through-drilled holes, and reduce faces that require flipping the part. Ordering multiple units at once also spreads the preparation cost.

The end mill is round, so the internal corners of a pocket always have a radius. Design radii of at least one-third the depth and never less than 1 mm: this allows using a larger, more rigid, and faster tool. If another part with sharp corners must fit there, add relief at the corners.

As a reference, 0.8 mm for metal and 1.5 mm for plastic. Below this, the wall vibrates during cutting and can deform or break. The higher the wall, the more thickness is advisable.

L ≤ 6 × D: recommended depth for blind holes with a standard drill. Maximum in this guide: 20 × D, with a long drill and through-tool coolant. Minimum diameter: 0.5 mm. Through holes have no depth warning up to 9 × D; from 20 to 40 × D, drill from both sides. For a thread, a usable length of 3 times the diameter is enough, from M3, with an unthreaded margin at the bottom. Since the 3D model doesn't show the thread size, mark the threads in a PDF attached to the part.

Only if the tool reaches the area. Hidden or closed cavities cannot be milled directly, and the usual alternative is to divide the part into two pieces joined with screws. The Proto&Go! engineering team reviews manufacturability when preparing the quote.

On the Proto&Go! resources page you can download the CNC machining design guide as a free PDF, in Spanish, English, French or Italian. It explains how the part is machined, how much tolerance to ask for, seven illustrated rules (inside radii, walls, drilled holes, threads, slots, undercuts and through holes), materials and finishes, and how to lower the cost.

The free PDF guide explains how an HP Multi Jet Fusion printer works, when to choose PA12 or TPA, size and tolerances, six illustrated rules (wall thickness, hollowing, holes, printed threads, inserts and text) and how to redesign, finish and assemble the part. You can download it in Spanish, English, French or Italian on the Proto&Go! resources page.

Yes. On the Proto&Go! resources page you can download the design guide for sheet metal cutting and bending as a free PDF, in Spanish, English, French or Italian. It explains how the part is laser-cut and bent from your 3D model, six illustrated rules (inside radius, minimum flange, holes near the bend, hole diameter, bend reliefs and fasteners), tolerances, materials and finishes, and which file to send.

The free PDF guide explains how the master and the silicone mold are made, which polyurethane to choose (rigid, flexible or transparent), tolerances, five illustrated rules (wall thickness, uniform thickness, ribs, undercuts and demolding, inserts and threads), color and finish, and how many parts each mold yields. You can download it in Spanish, English, French or Italian on the Proto&Go! resources page.

A wall thickness of at least 0.8 mm is recommended, although parts can be manufactured from 0.5 mm. Thinner walls may warp or break due to process heat. If a wall must be tall and thin, reinforce it with ribs.

For thicknesses over 10 mm in PA12, or 6 mm in TPA, it is advisable to hollow out the part. Heat concentrates in solid areas, and additionally, the price depends mainly on the powder volume. The standard practice is to leave a honeycomb filler with 3 mm walls and holes to remove the powder.

The recommended diameter is at least 1.5 mm. Holes as small as 0.8 mm can be manufactured.

Functional threads from M5, male and female, can be printed in MJF with 0.2 mm clearance: the screw with the nominal diameter minus 0.2 mm and the nut with the nominal diameter plus 0.2 mm. For threads from M3 to M8, metal inserts are the best solution.

In MJF, use a font of at least 6 points, with a height or depth of at least 1 mm and a stroke of 0.4 mm or more. Simple, sans-serif fonts are easier to read.

Use simple sans-serif fonts with thick, uniform strokes, and allow for slightly more size and depth if the part is to be sandblasted, anodized, painted, or polished: these finishes smooth the edges and reduce contrast. In machining, the inner radius of the letters depends on the end mill diameter. Simplify logos with very small details. For more details, see the article Engraved text and logos on prototypes.

As a reference, 1.5 to 3 mm works well for many plastic housings and prototypes. In machining, avoid walls under 1.5 mm in plastic and 0.8 mm in metal; in MJF printing with PA12, start from 1 to 2 mm. More than the exact value, it is important to maintain uniform thickness and rigidify with ribs rather than thickening the entire part. We explain this in how to prevent warping in 3D printing and CNC.

As a starting point, design a nominal wall thickness of 1.5 mm or more. Areas under 1 mm require specific review, as the minimum depends on the polyurethane resin, size, and fill path. Keep the thickness as uniform as possible and reinforce with ribs at 40 to 60% of the wall.

Yes. Silicone is flexible and admits many undercuts, but you must plan how to extract the part without damaging it or tearing the mold. Smooth out undercuts and add a draft angle when possible; the deepest ones may require cuts in the mold or detachable elements.

If the joint will be disassembled frequently, use metal inserts. They can be placed during casting or mounted afterward, depending on the insert and polyurethane. Indicate the reference, thread, position, and housing in a PDF drawing assigned to the part.

Because the silicone mold reproduces the texture and also the defects of the master on all parts. Define before mold fabrication which faces are visible and what finish they must have: smooth, matte, or textured. A master without marks reduces rework for the entire run.

Design an internal radius at least equal to the sheet metal thickness (r ≥ t). With smaller radii, the outer face of the bend stretches too much and may crack.

Give each flange at least four times the sheet metal thickness (≥ 4 × t). A shorter flange falls inside the press brake die and cannot be bent.

Separate drilled holes and slots from the bend line by at least two thicknesses plus the internal radius (≥ 2t + r); closer, they deform when bent. Additionally, the diameter of a drilled hole should not be less than the sheet metal thickness.

It is a cut at the end of a bend that does not reach the sheet metal edge and prevents tearing and deformations in that area. Give it a width of at least the thickness (t) and a depth of at least the thickness plus the internal radius (t + r).

The development is the flat sheet metal length before bending. For a part with one bend, it is calculated as L = A + B − BD, where A and B are the flanges and BD is the bend deduction, which depends on thickness, inner radius, angle, and K factor. At Proto&Go! you do not need to calculate it: upload the already bent 3D part and the development is obtained from the model. You can try the calculator on the sheet metal cutting and bending page.

Proto&Go! delivers parts with no finish or with sandblasting, anodizing, polishing, bluing, zinc plating, chrome plating, nickel plating, or RAL color painting. Each finish depends on the material: anodizing is for aluminum, while bluing and zinc plating are for steel.

Yes, slightly. Conventional anodizing forms a layer of 5 to 25 microns that grows about half outward and half inward into the metal: each face gains between 2.5 and 12.5 microns and a diameter, double, so a shaft thickens and a drilled hole narrows. Hard anodizing forms layers of 25 to 75 microns and changes dimensions more. For most parts it doesn't matter, but for a precise fit it's advisable to consider it when designing.

Special finishes, such as painting, optical polishing, or anodizing, must be specified when requesting a quote so they are included in the offer. The Proto&Go! comparator considers a standard finish, excluding VAT and shipping. Special finishes are quoted separately based on the part's requirements.

Anodizing is an electrochemical treatment that forms an oxide layer on the aluminum surface. It improves corrosion and wear resistance and allows coloring, for example black. It is applied to aluminum parts. Conventional anodizing forms a layer of 5 to 25 µm that grows about half outward, between 2.5 and 12.5 µm per side; hard anodizing reaches 25–75 µm. It is advisable to take this into account for precise fits.

These are metal finishes with different purposes. Zinc plating deposits zinc onto steel to protect it from corrosion. Bluing forms a thin black oxide layer on steel, with a dark appearance and moderate protection. Chrome plating and nickel plating deposit a shiny metallic layer that provides hardness, corrosion resistance, and a decorative appearance.

Sandblasting projects abrasive material under pressure onto the part, leaving a matte and uniform texture. It disguises machining marks and prepares the surface for anodizing or painting. It smooths edges and very fine details, such as small engraved text.

Yes. Machined and sheet metal parts can be painted in RAL color, with a matte, satin, or glossy finish. Vacuum cast polyurethane parts can be pigmented in bulk or painted in RAL or Pantone. Indicate the color code and finish when requesting the quote; painting is quoted separately.

PA12 parts printed in MJF are delivered with a natural gray finish or dyed black. If you need a different finish or a specific color, indicate it when requesting the quote so the team can evaluate the options.